Chapter 2: System Object Properties, Events, and Functions

BarcodeScanner base class

The BarcodeScanner is a base class for nonvisual objects that can read and process bar codes. The SymbolBarcodeScanner object and the SocketBarcodeScanner object implement all the methods and properties of this base class.

Properties

BarcodeScanner property	Datatype	Description
ScannerName	String	Name of the scanner you are using
ScannedData	String	Read-only data in the scanner’s internal buffers at the time of the last RetrieveData call
ScannedSymbology	Integer	Read-only value with the decoder ID representing the symbology used by the last data read by the scanner
ScannedTimeStamp	DateTime	Read-only timestamp of the last scan

Events

BarcodeScanner event	Occurs
Constructor	When the object is created
Destructor	When the object is destroyed
ScannerInserted	When the interface layer first recognizes a physical scanner: either on initialization of the scanner or on physical insertion of the scanner
ScannerRemoved	When the scanner is physically removed
ScanTriggered	When asynchronous data is scanned

Functions

BarcodeScanner function	Datatype returned	Description
Close	Integer	Optional method that clears all buffers, detaches from the scanner firmware, and unloads all scanning DLLs. By default, this method is called by the BarcodeScanner object destructor.
DecoderName	String	Retrieves the short decoder name for the ID value passed as a function argument.
DeviceInfo	Integer	Retrieves device-specific settings, such as version numbers.
DeviceNames	Integer	Sets the names of the scanning devices.
EnableDecoder	Integer	Enables or disables the decoder whose ID value is passed in a function argument.
Flush	Integer	Flushes any old results in the scan buffers.
GetEnabledDecoders	Integer	Gets the array of enabled decoders.
GetSupportedDecoders	Integer	Gets the array of supported decoders.
Open	Integer	Loads the scanning DLLs and connects to the scanner firmware. This is typically the first method called on an object instance.
RetrieveData	Integer	Retrieves the data from the scanner internal buffers.
ScanAbort	Integer	Aborts all outstanding scan requests.
ScanNoWait	Integer	Sets the scan for asynchronous operation and an immediate return of scan data. In a typical implementation of this method, the ScanTriggered event sets the rearm flag to “true” for continuous scanning.
ScanWait	Integer	Sets the timeout period for a synchronous scan. The timeout period is the amount of time allowed to elapse before a scan resumes following a pause in the scanning.
SoftTrigger	Boolean	Sets or retrieves the soft trigger feature of a scanner.
Status	Integer	Returns the scanner status as an integer.

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